A knee joint prosthesis with a universal ball shaft type anti-dislocation structure

Abstract

The present invention provides a knee joint prosthesis with a universal ball shaft type anti - dislocation structure, comprising: a femoral component, a tibial component, and a ball shaft connection component connecting the femoral component and the tibial component; the femoral component includes femoral condyles, the tibial component includes a tibial plateau and a tibial liner, and the femoral condyles contact the tibial liner to form an articular surface; the ball shaft connection component includes a universal ball shaft, one end of the universal ball shaft has a universal ball shaft hole, and the other end has a hemispherical universal ball, and a universal ball shaft neck is formed between the universal ball shaft hole and the hemispherical universal ball; the universal ball shaft is rotationally connected to the femoral condyles through the universal ball shaft hole. In the knee joint prosthesis of the present invention, an anti - dislocation snap ring and a universal ball shaft component with a posterior stability stop are added, which can not only meet the bionics of knee joint movement, the adaptation of mechanical properties, effectively disperse the stress of the knee joint prosthesis, but also prevent the knee joint from dislocating during movement, enhance the stability and anti - dislocation durability of the prosthesis, and further improve the service life of the prosthesis.

Description

Technical Field

[0001] The invention relates to the technical field of orthopedic medical instruments, and in particular to a tumor knee joint prosthesis containing a universal ball shaft and an anti-dislocation type. Background Art

[0002] The knee joint of the lower limb is a common site for malignant bone tumors. The current method for treating malignant bone tumors in this site is mainly to remove the diseased tumor segment and then reconstruct the large bone defect with an artificial hinge knee joint prosthesis.

[0003] At present, tumor-type artificial hinge knee joints have the following two major disadvantages:

[0004] 1 From a structural perspective: There are only two types of tumor-type knee prostheses: simple hinges and rotary hinges. These two simple structural designs greatly restrict the movement of the knee prosthesis in all directions, which is very different from the movement of the normal knee joint (flexion, extension, rotation, etc.), and cannot fully achieve the level of bionics. Therefore, this type of knee prosthesis has hidden dangers such as breakage, fatigue failure, severe wear, and periprosthetic fractures, especially in children and adolescents. The amount of knee joint movement in children and adolescents is greater than that in adults, and the bones gradually mature. Ordinary hinge knee joints are subject to the influence of stress in all directions of the bones during millions of knee joint movements. Ordinary hinge knee joints prevent dislocation of the knee joint by limiting the movement of the knee joint in all directions through the hinge, but this stability comes at the expense of movement.

[0005] During human activities, forces in all directions still exist. Therefore, in the process of long-term exercise, this prosthesis that does not conform to human kinematics will experience metal fatigue fracture, wear, and even fracture around the knee prosthesis. The same principle applies to the rotary hinge knee joint. It only has a rotation function compared to the ordinary hinge knee joint, and this rotation is mainly based on the rotation of the tibial plateau, which cannot truly achieve the purpose of bionics. Ultimately, under the action of stress in different directions, fatigue fracture will occur at the junction of the tibial plateau and the tibial pad.

[0006] 2. From the perspective of materials: Existing tumor knee prostheses mainly consist of a distal femur made of cobalt-chromium-molybdenum (CoCrMo) alloy, a tibial plateau and a medullary rod made of medical titanium alloy (Ti6Al4V), and a tibial pad made of polyethylene (PE). These two materials have excellent anti-wear performance and mechanical strength, and can provide immediate joint stability after implantation. However, as an implant prosthesis used in the orthopedic oncology department, it still has some deficiencies. First, the prosthesis made of cobalt-chromium-molybdenum (CoCrMo) alloy (density: 8.9 g / cm³) is too heavy, which will accelerate the load on the surrounding bone mass and may cause fractures and wear. Second, the metal particles generated during the wear process of cobalt-chromium-molybdenum (CoCrMo) alloy will cause inflammatory reactions and osteolysis in the surrounding tissues. Third, the elastic modulus of cobalt-chromium-molybdenum (CoCrMo) alloy (220 GPa) is much larger than that of human bone (3 - 20 GPa), and after implantation, it will cause the "stress shielding" effect, resulting in fatigue fractures of the prosthesis and fractures around the prosthesis. Finally, cobalt-chromium-molybdenum (CoCrMo) alloy will scatter after being irradiated by radiation on its surface, generating metal artifacts. On the one hand, these artifacts will affect the doctor's observation of tiny recurrent lesions during CT or X-ray examinations, resulting in irreparable consequences. On the other hand, during tumor radiotherapy, it will affect the estimation of radiation dose, and the scattered rays will also damage the surrounding normal tissues. Summary of the Invention

[0007] The present invention provides a knee prosthesis with a universal ball shaft type anti-dislocation function to solve the technical problems of fractures, dislocations, large weight, and poor light transmittance of knee prostheses.

[0008] The technical solution provided by the present invention is as follows:

[0009] An object of the present invention is to provide a knee prosthesis with a universal ball shaft type anti-dislocation function, the knee prosthesis comprising: a femoral component, a tibial component, and a ball shaft connection component connecting the femoral component and the tibial component;

[0010] The femoral component at least includes a femoral condyle, the tibial component at least includes a tibial plateau and a tibial liner, and the femoral condyle contacts the tibial liner to form a joint surface;

[0011] Wherein, the ball shaft connection component at least includes a universal ball shaft, one end of the universal ball shaft has a universal ball shaft hole, and the other end has a hemispherical universal ball, and a universal ball shaft neck is formed between the universal ball shaft hole and the hemispherical universal ball;

[0012] The universal ball shaft is rotatably connected to the femoral condyle through the universal ball shaft hole, so that the femoral condyle rotates relative to the tibial liner;

[0013] Wherein, a socket is formed on the tibial plateau; the hemispherical universal ball of the universal ball shaft is embedded into the socket of the tibial plateau, enabling the universal ball shaft to rotate 360° relative to the socket, thereby driving the femoral condyle to rotate 360°.

[0014] Wherein, a U-shaped groove is formed on the tibial insert; the width of the U-shaped groove is smaller than the diameter of the hemispherical universal ball; the tibial insert is installed on the tibial plateau, and the journal of the universal ball shaft is embedded into the U-shaped groove of the tibial insert, such that the tibial insert is located on the upper surface of the hemispherical universal ball to prevent the universal ball shaft from disengaging.

[0015] In a preferred embodiment, the ball shaft connection assembly further includes: a shaft pin and a locking pin.

[0016] A femoral condyle channel is formed on the femoral condyle; the axis of the femoral condyle channel is parallel to the axis of the universal ball shaft hole; an opening of the femoral condyle communicating with the femoral condyle channel is formed at the bottom of the femoral condyle.

[0017] When the universal ball shaft is rotatably connected to the femoral condyle through the universal ball shaft hole, the universal ball shaft is inserted into the opening of the femoral condyle, such that the axis of the universal ball shaft hole and the axis of the femoral condyle channel are in the same straight line.

[0018] The shaft pin is inserted into the femoral condyle channel and passes through the universal ball shaft hole, and the locking pin is inserted into the shaft pin and locked with the shaft pin, enabling the universal ball shaft to be rotatably connected to the femoral condyle through the universal ball shaft hole.

[0019] In a preferred embodiment, a shaft pin hole is formed at one end of the shaft pin; a cross-opening member is axially provided at one end of the locking pin; when the locking pin is inserted into the shaft pin, the cross-opening member is pressed into the shaft pin hole to lock the locking pin and the shaft pin.

[0020] In a preferred embodiment, a first PE liner and a second PE liner are installed between the shaft pin and the femoral condyle channel.

[0021] In a preferred embodiment, tibial insert hooks are provided at the bottom of the tibial insert, and tibial plateau slots are formed on the tibial plateau.

[0022] When the tibial insert is installed on the tibial plateau, the tibial insert and the tibial plateau are fixed by locking screws, and the tibial insert hooks are snapped into the tibial plateau slots.

[0023] In a preferred embodiment, U-shaped reinforcing ribs are provided in the U-shaped groove of the tibial insert, and U-shaped reinforcing rib grooves are formed on the U-shaped reinforcing ribs.

[0024] The width of the U-shaped reinforcing rib groove is smaller than the diameter of the hemispherical universal ball. When the tibial liner is mounted on the tibial plateau, the universal ball journal of the universal ball shaft is embedded in the U-shaped reinforcing rib groove of the U-shaped reinforcing rib. The U-shaped reinforcing rib is located on the upper surface of the hemispherical universal ball to prevent the universal ball shaft from disengaging and position it.

[0025] In a preferred embodiment, the width d of the U-shaped reinforcing rib groove is 12 mm, and the diameter D of the hemispherical universal ball is 22 mm.

[0026] When the tibial liner is mounted on the tibial plateau, the tibial liner forms an anti-disengagement interference amount of L = (D - d) / 2 = 5 mm on one side to prevent the universal ball shaft from disengaging and position it.

[0027] In a preferred embodiment, the ball shaft connection assembly further includes an anti-disengagement snap ring. The anti-disengagement snap ring has an anti-disengagement snap ring opening and is mounted on one side close to the upper surface of the hemispherical universal ball. A rear stabilizing block is provided at the position of the universal ball shaft where the universal ball journal is located.

[0028] When the hemispherical universal ball of the universal ball shaft is embedded in the ball socket of the tibial plateau, the anti-disengagement snap ring is embedded between the hemispherical universal ball and the ball socket.

[0029] Moreover, the rear stabilizing block is located on one side behind the tibial plateau, and the anti-disengagement snap ring opening of the anti-disengagement snap ring is located on one side in front of the tibial plateau.

[0030] The tibial liner is mounted on the tibial plateau, and the universal ball journal of the universal ball shaft is embedded in the U-shaped groove of the tibial liner. The tibial liner is located on the upper surface of the anti-disengagement snap ring to prevent the universal ball shaft from disengaging and position it.

[0031] In a preferred embodiment, the anti-disengagement snap ring has an anti-disengagement snap ring hook surrounding the anti-disengagement snap ring, and a ball socket card slot is formed on the inner surface of the ball socket.

[0032] When the anti-disengagement snap ring is embedded between the hemispherical universal ball and the ball socket, the anti-disengagement snap ring hook is snapped into the ball socket card slot.

[0033] In a preferred embodiment, the femoral component further includes a first shaft extension section and a medullary cavity extension stem. The first shaft extension section is connected to the femoral condyle, and the medullary cavity extension stem is connected to the first shaft extension section.

[0034] The tibial component further includes a medullary cavity stem, and the medullary cavity stem is connected to the tibial plateau.

[0035] Among them, the first backbone extension segment, the femoral condyle, and the universal ball shaft are prepared using carbon fiber modified polyetheretherketone material.

[0036] In a preferred embodiment, the femoral component further includes a medullary cavity extension stem, and the medullary cavity extension stem is connected to the femoral condyle;

[0037] The tibial component further includes a medullary cavity stem and a second backbone extension segment. The medullary cavity stem is connected to the second backbone extension segment, and the second backbone extension segment is connected to the tibial plateau;

[0038] Among them, the second backbone extension segment, the femoral condyle, and the universal ball shaft are prepared using carbon fiber modified polyetheretherketone material.

[0039] The above technical solution of the present invention has at least the following beneficial effects compared with the prior art:

[0040] The present invention provides a knee joint prosthesis with a universal ball shaft type anti - dislocation function, which can not only meet the bionic movement of the knee joint, adapt to the mechanical properties, effectively disperse the stress of the knee joint prosthesis, but also prevent the dislocation of the knee joint. The knee joint prosthesis material is lightweight, closer to the characteristics of the human bone, and has good light transmittance to meet the requirements of postoperative imaging examination.

[0041] The present invention provides a knee joint prosthesis with a universal ball shaft type anti - dislocation function, which solves the problem that the existing hinge knee joint does not match the biological movement of the normal human knee joint, and the multi - directional force causes wear, dislocation, and fatigue fracture of the knee joint prosthesis and other failure forms, resulting in a shortened service life of the knee joint prosthesis. In addition, through the improvement of the materials of the knee joint prosthesis components, the backbone extension segment, femoral condyle, and universal ball shaft made of cobalt - chromium - molybdenum (CoCrMo) alloy with a relatively large specific gravity are replaced with carbon fiber modified polyetheretherketone (CFR - PEEK) material with light weight, good mechanical properties, good light transmittance, and an elastic modulus closer to that of bone, overcoming the problems of fracture and wear caused by excessive weight in the existing tumor - type knee joint prosthesis, inflammatory reactions and osteolysis of surrounding tissues caused by metal particles, the "stress shielding" effect caused after the implantation of the knee joint prosthesis, and the defect of metal artifacts generated by radiation exposure.

[0042] The present invention provides a knee joint prosthesis with a universal ball shaft type anti - dislocation function. A ball - shaft connection component is introduced into the knee joint prosthesis. The ball - shaft connection component adopts a double - acting spherical surface fit, driving the femoral condyle to rotate 360°, which can effectively disperse the stress received by the knee joint prosthesis. At the same time, through the anti - dislocation design of the tibial liner, anti - dislocation limit is carried out on the ball - shaft connection component and the femoral condyle, reducing the dislocation during the movement of the knee joint prosthesis.

[0043] The present invention provides a knee joint prosthesis with a universal ball shaft and an anti-dislocation type. The shaft extension section, the femoral condyle and the universal ball shaft are made of carbon fiber modified polyetheretherketone (CFR-PEEK) material, so that the knee joint prosthesis has the advantages of light weight, good mechanical properties, good light transmittance, and an elastic modulus closer to that of bones, which reduces the load and wear of surrounding bones, can effectively avoid the "stress shielding" effect, reduce the risk of secondary fractures and bone loss, and can greatly increase the service life of the knee joint prosthesis. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0045] Figure 1 It is an exploded view of an anti-dislocation type knee joint prosthesis containing a universal ball shaft in the first embodiment of the present invention.

[0046] Figure 2 It is a front cross-sectional view of an anti-dislocation type knee joint prosthesis containing a universal ball shaft in Embodiment 1 of the present invention.

[0047] Figure 3 It is a schematic diagram of the coordinated installation of the shaft pin and the locking pin in the first embodiment of the present invention.

[0048] Figure 4 It is a side sectional view of an anti-dislocation type knee joint prosthesis containing a universal ball shaft in Embodiment 1 of the present invention.

[0049] Figure 5 yes Figure 4 Magnified view of area A in the middle.

[0050] Figure 6 It is a side cross-sectional view of a knee joint prosthesis containing a universal ball shaft and anti-dislocation type in a state of rotation and bending of the femoral condyle relative to the tibial pad in embodiment 1 of the present invention.

[0051] Figure 7 It is a schematic structural diagram of the tibial pad in the first embodiment of the present invention.

[0052] Figure 8 It is a front cross-sectional view of a knee joint prosthesis with a universal ball shaft and an anti-dislocation type in the second embodiment of the present invention.

[0053] Figure 9 yes Figure 8 Magnified view of area B in the middle.

[0054] Figure 10It is a schematic structural diagram of the anti - detachment snap ring in the second embodiment of the present invention.

[0055] Figure 11 It is Figure 9 an enlarged view of region C in

[0056] Figure 12 It is a side cross - sectional view of a knee joint prosthesis with a universal ball - shaft type anti - dislocation structure in the second embodiment of the present invention.

[0057] Figure 13 It is a schematic structural diagram of the universal ball - shaft in the second embodiment of the present invention.

[0058] Figure 14 It is Figure 12 an enlarged view of region E in

[0059] Figure 15 It is a side cross - sectional view of a knee joint prosthesis with a universal ball - shaft type anti - dislocation structure in the second embodiment of the present invention when the femoral condyle rotates and bends relative to the tibial insert.

[0060] Figure 16 It is a schematic diagram of the installation process of the anti - detachment snap ring and the universal ball - shaft in the second embodiment of the present invention.

[0061] Figure 17 It is a schematic diagram of the rotation process of the anti - detachment snap ring on one side of the upper surface of the hemispherical universal ball in the second embodiment of the present invention.

[0062] Figure 18 It is a schematic diagram of the hemispherical universal ball of the universal ball - shaft being embedded into the ball socket of the tibial plateau and the tibial insert being installed on the tibial plateau in the second embodiment of the present invention.

[0063] Figure 19 It is a finite - element model of a knee joint prosthesis made of carbon - fiber - reinforced polyether - ether - ketone (CFR - PEEK) material and a knee joint prosthesis made of cobalt - chromium - molybdenum (CoCrMo) alloy material in the present invention.

[0064] Figure 20 It is the calculation result of the finite - element simulation stress analysis of a knee joint prosthesis made of carbon - fiber - reinforced polyether - ether - ketone (CFR - PEEK) material and a knee joint prosthesis made of cobalt - chromium - molybdenum (CoCrMo) alloy material in the present invention.

[0065] Figure 21 It is the calculation result of the finite - element simulation stress analysis of a femoral condyle made of carbon - fiber - reinforced polyether - ether - ketone (CFR - PEEK) material and a femoral condyle made of cobalt - chromium - molybdenum (CoCrMo) alloy material in the present invention.

[0066] Figure 22It is the calculation result of the finite element simulation stress analysis of the universal ball shaft prepared from carbon fiber modified polyether ether ketone (CFR-PEEK) material and the universal ball shaft prepared from cobalt chromium molybdenum (CoCrMo) alloy material in the present invention.

[0067] Figure 23 It is an exploded view of a knee prosthesis with a universal ball shaft type anti-dislocation in the third embodiment of the present invention. Detailed implementation manners

[0068] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0069] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the art to which the present invention belongs. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, the terms such as "a", "an" or "the" do not denote a quantity limitation, but mean that there is at least one. The terms such as "comprising" or "including" mean that the elements or items appearing before this term cover the elements or items listed after this term and their equivalents, without excluding other elements or items. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0070] It should be noted that the "upper", "lower", "left", "right", "front", "rear", etc. used in the present invention are only used to represent relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly. Embodiment

[0071] Combined with Figures 1 to 7 , according to an embodiment of the present invention, there is provided a knee prosthesis with a universal ball shaft type anti-dislocation. The knee prosthesis includes: a femoral component 1, a tibial component 3, and a ball shaft connection component 2 connecting the femoral component 1 and the tibial component 3.

[0072] The femoral component 1 includes a femoral condyle 103, a first shaft extension segment 102, and a medullary cavity extension stem 101. The first shaft extension segment 102 is connected to the femoral condyle 103, and the medullary cavity extension stem 101 is connected to the first shaft extension segment 102.

[0073] The tibial component 3 includes a tibial plateau 302 , a tibial liner 303 and a medullary stem 301 . The medullary stem 301 is connected to the tibial plateau 302 .

[0074] like Figure 2 As shown, the tibial pad 303 is installed on the tibial platform 302, and the femoral condyle 103 contacts the tibial pad 303 to form an articulation surface. Specifically, the upper surface of the tibial pad 303 has an arc-shaped polished surface, and the arc-shaped polished surface of the tibial pad 303 and the femoral condyle 103 form an articulation surface.

[0075] The first diaphysis extension 102 of the present invention is made of carbon fiber modified polyether ether ketone (CFR-PEEK) material, the femoral condyle 103 is made of carbon fiber modified polyether ether ketone (CFR-PEEK) material, and the tibial liner 303 is made of polyethylene (PE) material. The tibial liner 303 made of polyethylene (PE) material effectively plays a role in buffering pressure. The tibial platform 302 of the present invention is made of cobalt chromium molybdenum (CoCrMo) alloy.

[0076] Combination Figure 1 and Figure 2 According to an embodiment of the present invention, the ball-shaft connection assembly 2 includes a universal ball shaft 201, a shaft pin 203 and a locking pin 202. The universal ball shaft 201 of the present invention is made of carbon fiber modified polyetheretherketone (CFR-PEEK) material.

[0077] One end of the universal ball shaft 201 has a universal ball shaft hole 2011 , and the other end has a hemispherical universal ball 2012 , and a universal ball shaft journal J is formed between the universal ball shaft hole 2011 and the hemispherical universal ball 2012 .

[0078] The universal ball shaft 201 is rotatably connected to the femoral condyle 103 through the universal ball shaft hole 2011 , so that the femoral condyle 103 can rotate and bend relative to the tibial pad 303 .

[0079] Specifically, combined Figure 1 , Figure 2 , Figure 4 and Figure 6 The femoral condyle 103 is provided with a femoral condyle channel 1031 , the axis of the femoral condyle channel 1031 is parallel to the axis of the universal ball shaft hole 2011 , and a femoral condyle opening K connected to the femoral condyle channel 1031 is provided at the bottom of the femoral condyle 103 .

[0080] When the universal ball shaft 201 is rotatably connected to the femoral condyle 103 through the universal ball shaft hole 2011, the universal ball shaft 201 is inserted into the femoral condyle opening K, so that the axis of the universal ball shaft hole 2011 is in the same straight line as the axis of the femoral condyle channel 1031. The shaft pin 203 is inserted into the femoral condyle channel 1031 and passes through the universal ball shaft hole 2011, and the locking pin 202 is inserted into the shaft pin 203 and locked with the shaft pin 203. At this time, the axis of the universal ball shaft hole 2011, the axis of the femoral condyle channel 1031, the axis of the locking pin 202, and the axis of the shaft pin 203 are in the same straight line, and the femoral condyle 103 rotates around the axis of the shaft pin 203 (the axis of the universal ball shaft hole 2011).

[0081] The present invention uses the shaft pin 203 and the locking pin 202 to lock, so that the universal ball shaft 201 is rotatably connected to the femoral condyle 103 through the universal ball shaft hole 2011. When the knee joint prosthesis is in the extended state, the femoral condyle 103 rotates and extends forward relative to the tibial insert 303 towards the front of the platform, as Figure 4 shown.

[0082] When the knee joint prosthesis is in the flexed state, the femoral condyle 103 rotates and bends backward relative to the tibial insert 303 towards the back of the platform, as Figure 6 shown.

[0083] In the present invention, the front of the platform refers to the front of the tibial platform 302, corresponding to the front of the knee joint prosthesis. The back of the platform in the present invention refers to the back of the tibial platform 302, corresponding to the back of the knee joint prosthesis.

[0084] As Figure 3 shown, according to an embodiment of the present invention, the shaft pin 203 has a stepped hole, a shaft pin hole 2031 is opened at one end of the shaft pin 203, a cross-opening member 2021 is axially arranged at one end of the locking pin 202, the cross-opening member 2021 is made of an elastic material titanium alloy, and the cross-opening member 2021 has an inverted tooth-shaped convex structure. When the locking pin 202 is inserted into the shaft pin 203, the cross-opening member 2021 is pressed into the shaft pin hole 2031 to lock the locking pin 202 and the shaft pin 203, preventing the locking pin 202 and the shaft pin 203 from being displaced from each other.

[0085] Furthermore, a first PE liner 104 and a second PE liner 105 are installed between the shaft pin 203 and the femoral condyle channel 1031, as Figure 1 and Figure 2 shown.

[0086] Combined with Figure 2 、 Figure 4 、 Figure 6 and Figure 7, according to an embodiment of the present invention, a ball socket 3021 is formed on the tibial plateau 302. The hemispherical universal ball 2012 and the ball socket 3021 are polished. The hemispherical universal ball 2012 of the universal ball shaft 201 is embedded into the ball socket 3021 of the tibial plateau 302, enabling the universal ball shaft 201 to rotate 360° relative to the ball socket 3021, thereby driving the femoral condyle 103 to rotate 360°.

[0087] As Figure 7 shown, a U-shaped groove 3031 is formed on the tibial insert 303. The width of the U-shaped groove 3031 is smaller than the diameter of the hemispherical universal ball 2021. The tibial insert 303 is installed on the tibial plateau 302, and the journal J of the universal ball shaft 201 is embedded into the U-shaped groove 3031 of the tibial insert 303, positioning the tibial insert 303 on the upper surface of the hemispherical universal ball 2012 to prevent the universal ball shaft 201 from coming off, as Figure 2 shown.

[0088] Further, in combination with Figure 2 and Figure 7 , the U-shaped groove 3031 of the tibial insert 303 has a U-shaped reinforcing rib 3032 with a U-shaped reinforcing rib groove 3033. The width of the U-shaped reinforcing rib groove 3033 is smaller than the diameter of the hemispherical universal ball 2012. When the tibial insert 303 is installed on the tibial plateau 302, the journal J of the universal ball shaft 201 is embedded into the U-shaped reinforcing rib groove 3033 of the U-shaped reinforcing rib 3032, and the U-shaped reinforcing rib 3032 is located on the upper surface of the hemispherical universal ball 2012 to prevent the universal ball shaft 201 from coming off.

[0089] Preferably, as Figure 2 shown, the width d of the U-shaped reinforcing rib groove 3033 is 12 mm, and the diameter D of the hemispherical universal ball 2012 is 22 mm. When the tibial insert 303 is installed on the tibial plateau 302, the tibial insert 303 forms a unilateral (one-sided) anti-disengagement interference amount of L = (D - d) / 2 = 5 mm to prevent the universal ball shaft 201 from coming off.

[0090] Further, a gap of 0.5 - 1 mm is left at the positions where the U-shaped reinforcing rib groove 3033 is in contact with the journal J of the universal ball shaft 201.

[0091] As Figure 5 shown, according to an embodiment of the present invention, a tibial insert hook 3034 is provided at the bottom of the tibial insert 303, and a tibial plateau card slot 3022 is formed on the tibial plateau 302. When the tibial insert 303 is installed on the tibial plateau 302, the tibial insert 303 and the tibial plateau 302 are fixed by a locking screw 304, and the tibial insert hook 3034 is snapped into the tibial plateau card slot 3022.

[0092] In the present invention, the femoral component 1 and the tibial component 3 are connected by a ball and shaft connection component 2. The universal ball and shaft 201 completely subverts the design of knee joint prostheses in the prior art. The hemispherical universal ball 2012 and the ball socket 3021 are polished. The hemispherical universal ball 2012 of the universal ball and shaft 201 is embedded in the ball socket 3021 of the tibial plateau 302 to achieve a double-acting spherical surface fit, enabling the universal ball and shaft 201 to rotate 360° (360° micro-movement) relative to the ball socket 3021, thereby driving the femoral condyle 103 to rotate 360° (360° micro-movement). While increasing the mobility of the knee joint prosthesis, it can also reduce the stress on the femoral component 1 and the tibial component 3 of the knee joint prosthesis during knee joint movement, slow down the loosening of the knee joint prosthesis, greatly enhance the service life of the knee joint prosthesis, and more conform to the kinematic laws of the normal human knee joint, achieving a fully bionic effect.

[0093] In the present invention, the hemispherical universal ball 2012 and the ball socket 3021 have a double-acting spherical surface fit. The hemispherical universal ball 2012 and the ball socket 3021 are polished. The hemispherical universal ball 2012 made of carbon fiber-reinforced polyether ether ketone (CFR-PEEK) material and the ball socket 3021 made of cobalt-chromium-molybdenum (CoCrMo) alloy have a double-acting spherical surface fit, effectively reducing the mutual wear between the hemispherical universal ball 2012 and the tibial plateau 302 during movement.

[0094] In the present invention, the U-shaped groove 3031 of the tibial liner 303 has a U-shaped reinforcing rib 3032. The U-shaped reinforcing rib 3032 has a U-shaped reinforcing rib groove 3033. The width d of the U-shaped reinforcing rib groove 3033 is 12 mm, and the diameter D of the hemispherical universal ball 2012 is 22 mm. The tibial liner 303 forms a unilateral anti-detachment interference amount of L = (D - d) / 2 = 5 mm. The tibial liner 303 and the tibial plateau 302 are fixed by a locking screw 304, and the tibial liner hook 3034 is snapped into the tibial plateau card slot 3022. The tibial liner 303 and the U-shaped reinforcing rib 3032 are located on the upper surface of the hemispherical universal ball 2012 to press the hemispherical universal ball 2012, providing anti-detachment limit for the universal ball and shaft 201, ensuring that the universal ball and shaft 201 rotates 360° relative to the ball socket 3021, perfectly coping with the stress generated during sudden start running, lateral movement, and rotation movements of the human body, greatly enhancing the service life of the knee joint prosthesis, and more conforming to the kinematic laws of the normal human knee joint, achieving a fully bionic effect.

[0095] In addition, a gap of 0.5 - 1 mm is left at the position where the U-shaped reinforcing rib groove 3033 is connected to the universal ball shaft neck J of the universal ball and shaft 201, so that a gap of 0.5 - 1 mm is left at the position where the tibial liner 303 is connected to the universal ball and shaft 201. The limitation of this appropriate gap can also ensure the anti-detachment stability of the knee joint prosthesis and the gait stability during movement.

[0096] In the present invention, the femoral component 1 and the tibial component 3 are connected by a ball-and-axis connection component 2 to achieve the bionic movement function of the knee joint prosthesis. The universal ball-and-axis 201 of the ball-and-axis connection component 2 and the femoral condyle 103 of the femoral component 1 are rotationally connected through a shaft pin 203 and a locking pin 202 such that the universal ball-and-axis 201 passes through a universal ball-and-axis hole 2011 and the femoral condyle 103. The anti-disengagement stability of the shaft pin 203 and the locking pin 202 is also an important factor determining the non-dislocation failure of the knee joint prosthesis. One end of the locking pin 202 of the present invention is axially provided with a cross-opening member 2021. The cross-opening member 2021 is made of an elastic material, titanium alloy. The cross-opening member 2021 is pressed into a shaft pin hole 2031. Under the elastic action of the cross-opening member 2021, the locking pin 202 and the shaft pin 203 are locked to prevent the dislocation of the locking pin 202 and the shaft pin 203. After 5 million times of simulated knee joint prosthesis flexion fatigue tests, the locking pin 202 did not produce dislocation failure. Embodiment

[0097] The difference between this embodiment and the first embodiment is that an anti-disengagement snap ring 2013 is installed on one side close to the upper surface of the hemispherical universal ball 2012. A post-stabilizing block 2014 is provided at the position of the universal ball-and-axis neck J where the universal ball-and-axis 201 is located.

[0098] Combined with Figures 8 to 15 , according to an embodiment of the present invention, the ball-and-axis connection component 2 further includes an anti-disengagement snap ring 2013. The anti-disengagement snap ring 2013 has an anti-disengagement snap ring hook 20131 surrounding the anti-disengagement snap ring 2013 and an anti-disengagement snap ring opening 20132. The anti-disengagement snap ring 2013 is prepared from a titanium alloy material, as Figure 10 shown.

[0099] Combined with Figure 8 , Figure 9 , Figure 10 , Figure 11 , Figure 12 , Figure 14 and Figure 15 , the inner surface of the anti-disengagement snap ring 2013 has a polished arc surface adapted to the hemispherical universal ball 2012. The anti-disengagement snap ring 2013 is installed on one side close to the upper surface of the hemispherical universal ball 2012.

[0100] As Figure 12 , Figure 13 and Figure 15 shown, a post-stabilizing block 2014 is provided at the position of the universal ball-and-axis neck J where the universal ball-and-axis 201 is located.

[0101] When the hemispherical universal ball 2012 of the universal ball shaft 201 is embedded in the ball socket 3021 of the tibial platform 302, the anti-slip ring 2013 is embedded between the hemispherical universal ball 2012 and the ball socket 3021, and the rear stabilizing block 2014 is located on the rear side of the platform, and the anti-slip ring opening 20132 of the anti-slip ring 2013 is located on the front side of the platform.

[0102] like Figure 9 As shown, the tibial pad 303 is installed on the tibial platform 302, and the universal ball shaft neck J of the universal ball shaft 201 is embedded in the U-shaped groove 3031 of the tibial pad 303. The tibial pad 303 is located on the upper surface of the anti-dropout clamp 2013 to prevent the universal ball shaft from dropping out.

[0103] Furthermore, when the tibial pad 303 is installed on the tibial platform 302, the universal ball shaft neck J of the universal ball shaft 201 is embedded in the U-shaped reinforcement groove 3033 of the U-shaped reinforcement rib 3032. The U-shaped reinforcement rib 3032 is located on the upper surface of the hemispherical universal ball 2012 to prevent the universal ball shaft 201 from falling off.

[0104] like Figure 11 and Figure 14 According to an embodiment of the present invention, a ball socket groove 3023 is provided on the inner surface of the ball socket 3021 of the tibial platform 302. When the anti-dropping snap ring 2013 is embedded between the hemispherical universal ball 2012 and the ball socket 3021, the anti-dropping snap ring hook 20131 is inserted into the ball socket groove 3023.

[0105] For patients with large amount of exercise and large range of motion (such as adolescents, children, manual laborers and other patients), the risk of knee joint prosthesis dislocation increases. In this embodiment, an anti-dropout clamp 213 is embedded between the hemispherical universal ball 2012 and the ball socket 3021, and the anti-dropout clamp 213 protects the hemispherical universal ball 2012 made of carbon fiber modified polyetheretherketone (CFR-PEEK) material. At the same time, the universal ball shaft 201 is located at the position of the universal ball shaft neck J and a rear stabilizing block 2014 is set. The rear stabilizing block 303 is located on one side of the rear of the platform, and the anti-dropout clamp opening 20132 of the anti-dropout clamp 2013 is located on one side of the front of the platform, which effectively prevents the hemispherical universal ball 2012 from falling out, and the universal ball shaft 201 is anti-dropout and limited, so that the knee joint prosthesis has better stability during knee flexion movement, and the anti-dropout performance is also further enhanced.

[0106] In order to ensure the anti-dislocation function of the knee joint prosthesis in this embodiment, each component needs to be assembled according to the correct steps during clinical installation and implantation.

[0107] Combination Figures 16 to 18 During the assembly of the knee joint prosthesis, the anti-dropping clamp 2013 is first installed on one side of the upper surface of the hemispherical universal ball 2012 close to the universal ball shaft 201, such as Figure 16As shown. Then rotate the anti - detachment snap ring 2013 so that the anti - detachment snap ring opening 20132 of the anti - detachment snap ring 2013 is in the opposite position to the rear stabilizing stop 2014, as Figure 17 shown.

[0108] Subsequently, embed the hemispherical universal ball 2012 of the universal ball shaft 201 into the ball socket 3021 of the tibial plateau 302, so that the anti - detachment snap ring 2013 is embedded between the hemispherical universal ball 2012 and the ball socket 3021, and the anti - detachment snap ring hook 20131 is snapped into the ball socket slot 3023. At the same time, the rear stabilizing stop 2014 is located on one side behind the platform, and the anti - detachment snap ring opening 20132 of the anti - detachment snap ring 2013 is located on one side in front of the platform.

[0109] Subsequently, push the U - shaped groove 3031 of the tibial insert 303 towards the universal ball shaft neck J of the universal ball shaft 201. The universal ball shaft neck J of the universal ball shaft 201 is embedded into the U - shaped rib groove 3033 of the U - shaped rib 3032 of the tibial insert 303. The tibial insert 303 is located on the upper surface of the anti - detachment snap ring 2013, and the U - shaped rib 3032 is located on the upper surface of the hemispherical universal ball 2012 to prevent the universal ball shaft 201 from detaching, as Figure 18 shown.

[0110] Finally, insert the universal ball shaft 201 into the femoral condyle 103 so that the axis of the universal ball shaft hole 2011 is in the same straight line as the axis of the femoral condyle channel. The pin 203 is inserted into the femoral condyle channel and passes through the universal ball shaft hole 2011, and the locking pin 202 is inserted into the pin 203 and locked with the pin 203. The universal ball shaft 201 is rotationally connected to the femoral condyle 103 through the universal ball shaft hole 2011 by using the pin 203 and the locking pin 202.

[0111] The other structures of this embodiment are the same as those of Embodiment 1 and will not be elaborated here. The connection method between the tibial plateau 302 and the tibial insert 303 is the same as that of Embodiment 1 and will not be elaborated here.

[0112] The multiple anti - dislocation designs (anti - detachment snap ring 2013, U - shaped rib 3032, rear stabilizing baffle 2014, elastic anti - detachment pin 203 and locking pin 202 structures) of the universal ball shaft assembly 2 in the present invention make the knee joint prosthesis have better stability during flexion movement, and the anti - detachment performance is further enhanced, effectively preventing the risk of knee joint prosthesis dislocation failure and greatly enhancing the service life of the knee joint prosthesis.

[0113] In Embodiment 1 and Embodiment 2 of the present invention, the first shaft extension segment 102 is made of carbon fiber modified polyetheretherketone (CFR-PEEK) material, the femoral condyle 103 is made of carbon fiber modified polyetheretherketone (CFR-PEEK) material, the universal ball shaft 201 is made of carbon fiber modified polyetheretherketone (CFR-PEEK) material, the tibial pad 303 is made of polyethylene (PE) material, and the tibial platform 302 is made of cobalt-chromium-molybdenum (CoCrMo) alloy.

[0114] The present invention replaces the existing femoral condyle 103 and the first diaphyseal extension 102 of the cobalt-chromium-molybdenum (CoCrMo) alloy with a large specific gravity and a large elastic modulus with a carbon fiber modified polyetheretherketone (CFR-PEEK) material with a light weight, good mechanical properties, good light transmittance, and an elastic modulus closer to that of bones. At the same time, the universal ball shaft 201 is prepared using the carbon fiber modified polyetheretherketone (CFR-PEEK) material, so that the knee joint prosthesis can not only ensure that the required mechanical properties are met, but also the weight of the knee joint prosthesis is greatly reduced, the load and wear of the surrounding bones are reduced, and it is beneficial to the early immediate stability of the knee joint prosthesis. In addition, the carbon fiber modified polyetheretherketone (CFR-PEEK) material has good biocompatibility with human bones, and its wear particles are less toxic, so that the knee joint prosthesis of the present invention can effectively avoid the "stress shielding" effect, reduce the risk of secondary fractures and bone loss, and avoid causing inflammatory reactions in the tissues around the knee joint prosthesis.

[0115] The present invention uses a first diaphysis extension segment 102, a femoral condyle 103, and a universal ball shaft 201 made of carbon fiber modified polyetheretherketone (CFR-PEEK) material and a knee joint prosthesis made of a first diaphysis extension segment 102, a femoral condyle 103, and a universal ball shaft 201 made of cobalt-chromium-molybdenum (CoCrMo) alloy material to perform finite element simulation post-implantation stress analysis.

[0116] Finite element model such as Figure 19 As shown, Figure 19 (a) is a knee joint prosthesis model made of cobalt-chromium-molybdenum (CoCrMo) alloy material, including a first diaphysis extension 102, a femoral condyle 103, and a universal ball shaft 201. Figure 19 Middle (b) is a knee joint prosthesis comprising a first diaphysis extension section 102 , a femoral condyle 103 , and a universal ball shaft 201 made of the carbon fiber modified polyetheretherketone (CFR-PEEK) material of the present invention.

[0117] The calculation results of the finite element simulation stress analysis (Mises equivalent stress analysis) of the knee prosthesis are as follows: Figure 20 As shown, Figure 20 (a) is the calculation result of finite element simulation stress analysis of the knee joint prosthesis made of cobalt-chromium-molybdenum (CoCrMo) alloy material, including the first diaphysis extension 102, the femoral condyle 103, and the universal ball shaft 201.Figure 20 In (b) is the calculation result of the finite element simulation stress analysis of the knee joint prosthesis of the first backbone extension segment 102, femoral condyle 103, and universal ball shaft 201 prepared from the carbon fiber modified polyetheretherketone (CFR-PEEK) material of the present invention.

[0118] The calculation result of the finite element simulation stress analysis (von Mises equivalent stress analysis) of the femoral condyle 103 is as Figure 21 shown. Figure 21 In (a) is the calculation result of the finite element simulation stress analysis of the femoral condyle 103 prepared from the cobalt-chromium-molybdenum (CoCrMo) alloy material. Figure 21 In (b) is the calculation result of the finite element simulation stress analysis of the femoral condyle 103 prepared from the carbon fiber modified polyetheretherketone (CFR-PEEK) material of the present invention.

[0119] The calculation result of the finite element simulation stress analysis (von Mises equivalent stress analysis) of the universal ball shaft 201 is as Figure 22 shown. Figure 22 In (a) is the calculation result of the finite element simulation stress analysis of the universal ball shaft 201 prepared from the cobalt-chromium-molybdenum (CoCrMo) alloy material. Figure 22 In (b) is the calculation result of the finite element simulation stress analysis of the universal ball shaft 201 prepared from the carbon fiber modified polyetheretherketone (CFR-PEEK) material of the present invention.

[0120] The calculation result of the finite element simulation stress analysis shows that the knee joint prosthesis of the first backbone extension segment 102, femoral condyle 103, and universal ball shaft 201 prepared from the carbon fiber modified polyetheretherketone (CFR-PEEK) material of the present invention can effectively reduce the stress concentration on the bone and the knee joint prosthesis, making the stress distribution on the knee joint prosthesis and the bone more reasonable and closer to the original biomechanical characteristics of the bone.

[0121] The carbon fiber modified polyetheretherketone (CFR-PEEK) material used in the present invention has good mechanical strength (compressive strength, bending strength, yield stress, impact strength) and biosafety. Compared with metals, on the one hand, the carbon fiber modified polyetheretherketone (CFR-PEEK) material has a lower density. The density of the carbon fiber modified polyetheretherketone (CFR-PEEK) material is only about 1.38g / cm3. When used as a knee joint prosthesis, it can effectively reduce the weight of the prosthesis, reduce the weight of the implant, and reduce the burden on the host bone, which is beneficial to the early immediate stability of the prosthesis; on the other hand, the elastic modulus (about 18Gpa) of the carbon fiber modified polyetheretherketone (CFR-PEEK) material is similar to the elastic modulus of human bones (3-20GPa), which is lower than medical titanium alloy (110GPa). Therefore, after being implanted into the human body, it can effectively avoid the stress shielding effect and reduce the risk of secondary fractures and bone loss. Thirdly, the wear particles of carbon fiber modified polyetheretherketone (CFR-PEEK) material are not as tissue toxic as the wear particles of CoCrMo alloy.

[0122] The carbon fiber modified polyetheretherketone (CFR-PEEK) material used in the present invention has excellent light transmittance, which makes it have very important application value in the field of orthopedics, especially bone tumors. The carbon fiber modified polyetheretherketone (CFR-PEEK) material eliminates the interference of metal artifacts, which can help doctors detect early tumor recurrence; in addition, the carbon fiber modified polyetheretherketone (CFR-PEEK) material can also solve the problem of ray refraction. After the problem of ray refraction is solved, on the one hand, orthopedic surgeons can more accurately judge the dose of radiotherapy, and on the other hand, the surrounding tissues are better protected. The carbon fiber modified polyetheretherketone (CFR-PEEK) material provides a very good alternative solution to solve the problem of tissue inflammation caused by the release of metal ions during the wear of cobalt-chromium-molybdenum (CoCrMo) alloy knee prosthesis. Example

[0123] The difference between this embodiment and the first and second embodiments is that the femoral component 1 does not have a first diaphysis extension section, and the tibial component 3 includes a second diaphysis extension section 305 .

[0124] In the first and second embodiments, the present invention provides a kind of knee joint prosthesis with a universal ball shaft type anti-dislocation type, which is applied to the case of malignant bone tumors in the distal and middle parts of the femur. In this embodiment, the present invention provides a kind of knee joint prosthesis with a universal ball shaft type anti-dislocation type, which is applied to the case of malignant bone tumors in the proximal and middle parts of the tibia.

[0125] Combination Figure 23According to an embodiment of the present invention, a universal ball-shaft anti-dislocation knee joint prosthesis comprises: a femoral component 1, a tibial component 3, and a ball-shaft connection component 2 connecting the femoral component 1 and the tibial component 3.

[0126] The femoral component 1 includes a femoral condyle 103 and a medullary cavity extension stem 101 , and the medullary cavity extension stem 101 is connected to the femoral condyle 103 .

[0127] The tibial component 3 includes a tibial plateau 302 , a tibial liner 303 , a second diaphysis extension section 305 and a medullary stem 301 . The medullary stem 301 is connected to the second diaphysis extension section 305 , and the second diaphysis extension section 305 is connected to the tibial plateau 302 .

[0128] The tibial pad 303 is mounted on the tibial platform 302, and the femoral condyle 103 contacts the tibial pad 303 to form an articulation surface. Specifically, the upper surface of the tibial pad 303 has an arc-shaped polished surface, and the arc-shaped polished surface of the tibial pad 303 and the femoral condyle 103 form an articulation surface.

[0129] In this embodiment, the second bone extension section 305, the femoral condyle 103 and the universal ball shaft 201 are made of carbon fiber modified polyetheretherketone (CFR-PEEK) material.

[0130] The other structures of this embodiment are the same as those of Embodiment 1 and Embodiment 2, and will not be described again here.

[0131] There are a few points to note:

[0132] (1) The drawings of the embodiments of the present invention only involve structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0133] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness of layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0134] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0135] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A knee joint prosthesis with a universal ball shaft type anti - dislocation feature, characterized in that, The knee joint prosthesis includes: a femoral component, a tibial component, and a ball-and-shaft connection component connecting the femoral component and the tibial component; The femoral component at least includes a femoral condyle, the tibial component at least includes a tibial plateau and a tibial liner, and the femoral condyle contacts the tibial liner to form a joint surface; Wherein, the ball-and-shaft connection component at least includes a universal ball-and-shaft. One end of the universal ball-and-shaft has a universal ball-and-shaft hole, and the other end has a hemispherical universal ball. A universal ball-and-shaft neck is formed between the universal ball-and-shaft hole and the hemispherical universal ball; The universal ball-and-shaft is rotatably connected to the femoral condyle through the universal ball-and-shaft hole, so that the femoral condyle rotates relative to the tibial liner; Wherein, a ball socket is formed on the tibial plateau; the hemispherical universal ball of the universal ball-and-shaft is embedded into the ball socket of the tibial plateau, so that the universal ball-and-shaft can rotate 360° relative to the ball socket, thereby driving the femoral condyle to rotate 360°; Wherein, a U-shaped groove is formed on the tibial liner, and the width of the U-shaped groove is smaller than the diameter of the hemispherical universal ball; the tibial liner is installed on the tibial plateau, and the universal ball-and-shaft neck of the universal ball-and-shaft is embedded into the U-shaped groove of the tibial liner, so that the tibial liner is located on the upper surface of the hemispherical universal ball to prevent the universal ball-and-shaft from disengaging; The ball-and-shaft connection component further includes an anti-disengagement snap ring. The anti-disengagement snap ring has an anti-disengagement snap ring opening, and the anti-disengagement snap ring is installed on one side close to the upper surface of the hemispherical universal ball; a rear stabilizing block is arranged at the position of the universal ball-and-shaft where the universal ball-and-shaft neck is located; When the hemispherical universal ball of the universal ball-and-shaft is embedded into the ball socket of the tibial plateau, the anti-disengagement snap ring is embedded between the hemispherical universal ball and the ball socket; And, the rear stabilizing block is located on one side behind the tibial plateau, and the anti-disengagement snap ring opening of the anti-disengagement snap ring is located on one side in front of the tibial plateau, effectively preventing the hemispherical universal ball from disengaging and preventing the universal ball-and-shaft from disengaging; The tibial liner is installed on the tibial plateau, and the universal ball-and-shaft neck of the universal ball-and-shaft is embedded into the U-shaped groove of the tibial liner. The tibial liner is located on the upper surface of the anti-disengagement snap ring to prevent the universal ball-and-shaft from disengaging; The anti-disengagement snap ring has an anti-disengagement snap ring hook surrounding the anti-disengagement snap ring, and a ball socket card slot is formed on the inner surface of the ball socket; When the anti-disengagement snap ring is embedded between the hemispherical universal ball and the ball socket, the anti-disengagement snap ring hook is snapped into the ball socket card slot; the anti-disengagement snap ring is made of titanium alloy material, and the inner surface of the anti-disengagement snap ring has a polished arc surface adapted to the hemispherical universal ball. The anti-disengagement snap ring is installed on one side close to the upper surface of the hemispherical universal ball; The U-shaped groove of the tibial pad is provided with a U-shaped reinforcing rib, and the U-shaped reinforcing rib has a U-shaped reinforcing rib groove; the width of the U-shaped reinforcing rib groove is smaller than the diameter of the hemispherical universal ball, and when the tibial pad is installed on the tibial platform, the universal ball shaft neck of the universal ball shaft is embedded in the U-shaped reinforcing rib groove of the U-shaped reinforcing rib, and the U-shaped reinforcing rib is located on the upper surface of the hemispherical universal ball to prevent the universal ball shaft from falling off and limiting the position; A tibial pad hook is provided at the bottom of the tibial pad, and a tibial plateau slot is provided on the tibial plateau; when the tibial pad is installed on the tibial plateau, the tibial pad and the tibial plateau are fixed by a locking screw, and the tibial pad hook is inserted into the tibial plateau slot; The ball-shaft connection assembly also includes: an axle pin and a locking pin; the axle pin is inserted into the femoral condyle channel and passes through the universal ball shaft hole, and the locking pin is inserted into the axle pin and locked with the axle pin, so that the universal ball shaft is rotationally connected to the femoral condyle through the universal ball shaft hole.

2. The knee joint prosthesis with a universal ball shaft type anti - dislocation feature according to claim 1, characterized in that, The femoral condyle is provided with a femoral condyle channel, the axis of the femoral condyle channel is parallel to the axis of the universal ball shaft hole; the bottom of the femoral condyle is provided with a femoral condyle opening connected with the femoral condyle channel; When the universal ball shaft is rotationally connected to the femoral condyle through the universal ball shaft hole, the universal ball shaft is inserted into the femoral condyle opening so that the axis of the universal ball shaft hole and the axis of the femoral condyle channel are in the same straight line.

3. The knee joint prosthesis with a universal ball shaft type anti - dislocation feature according to claim 2, wherein, An axis pin hole is provided at one end of the axis pin, and a cross opening piece is axially arranged at one end of the locking pin; when the locking pin is inserted into the axis pin, the cross opening piece is pressed into the axis pin hole to lock the locking pin and the axis pin.

4. The knee joint prosthesis with a universal ball shaft type anti-dislocation feature according to claim 2, characterized in that, A first PE liner and a second PE liner are installed between the shaft pin and the femoral condyle channel.

5. The knee joint prosthesis with a universal ball shaft type anti-dislocation feature according to claim 1, characterized in that, The width d of the U-shaped reinforcing rib groove is 12 mm, and the diameter D of the hemispherical universal ball is 22 mm; When the tibial pad is installed on the tibial platform, the tibial pad forms an anti-slip interference amount of L=(D-d) / 2=5 mm on one side, and the universal ball shaft is prevented from slipping.

6. The knee joint prosthesis with a universal ball shaft type anti - dislocation feature according to claim 1, characterized in that, The femoral component further comprises a first diaphysis extension section and a medullary cavity extension handle, wherein the first diaphysis extension section is connected to the femoral condyle, and the medullary cavity extension handle is connected to the first diaphysis extension section; The tibial component also includes a medullary stem connected to the tibial plateau; Wherein, the first bone shaft extension section, the femoral condyle and the universal ball shaft are made of carbon fiber modified polyetheretherketone material.

7. The knee joint prosthesis with a universal ball shaft type anti-dislocation feature according to claim 1, characterized in that, The femoral component also includes a medullary cavity extension handle, and the medullary cavity extension handle is connected to the femoral condyle; The tibial component further comprises a medullary stem and a second diaphysis extension segment, wherein the medullary stem is connected to the second diaphysis extension segment, and the second diaphysis extension segment is connected to the tibial plateau; Wherein, the second diaphysis extension section, the femoral condyle and the universal ball shaft are made of carbon fiber modified polyetheretherketone material.

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